RICHMOND, Texas (CBSDFW.COM/AP) — A counselor who works in a Texas prison has tested positive for COVID-19, marking the first time the disease caused by the coronavirus has been reported in the country’s largest prison system.

The substance abuse counselor found out he tested positive for the disease Sunday after doing “cell side counseling” at a prison outside of Houston last week, a Texas Department of Criminal Justice spokesman said Monday.

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The counselor, an employee of the Management and Training Corporation, has been ordered into quarantine. The prisoners who had “limited contact” with the counselor through “hard cell doors” are in a restrictive housing unit, spokesman Jeremy Desel said in statement.

The counseling took place through a locked door and involved “no physical contact,” Desel said.

The 300-person prison where the counselor was working is in Richmond and houses people with substance-abuse disorder.

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The counselor passed an “unit entry screening” last Tuesday before going to work and attending a training with other employees from his company. The counselor went home early that day and saw a doctor, who approved him to return to work at the prison, which he did Saturday, Desel said.

Desel said the counselor was unaware he’d been tested for COVID-19 before receiving the results. The other MTC employees who were at the training with the counselor are also in quarantine and no one who had contact with him is currently symptomatic, Desel said.

The vast majority of people who contract the virus recover within weeks. It causes only mild or moderate symptoms for most people, but it can lead to more severe illness, including pneumonia, especially in older adults and people with preexisting health problems.

(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)

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